The bar association objects to the planned transformation of the Canadian Security Intelligence Service into an agency that could actively disrupt terror plots.
It argues the bill's "vague and overly broad language" would capture legitimate activity, including environmental and aboriginal protests — and possibly put a chill on expressions of dissent.
The most worrying element of the bill is a provision that would give judges the power to authorize CSIS violations of the Charter of Rights and Freedoms, the association says.
It potentially brings "the entire Charter into jeopardy, undermines the rule of law, and goes against the fundamental role of judges as the protectors of Canada's constitutional rights."
The association wants a sunset clause that would see the bill expire and trigger a parliamentary review no more than five years after its passage.
The association, which represents more than 36,000 lawyers across Canada, released a draft summary of its concerns Friday. It has developed a full submission drawing on the input of experts in criminal, immigration, privacy and charities law.
Association representatives are scheduled to appear before the House of Commons committee studying the bill next week.
The government argues the proposed new provisions are needed to combat the threat of homegrown terrorism in the wake of two murders of Canadian soldiers last October.
The bill would also make it easier for police to limit the movements of a suspect, expand no-fly list powers and take aim at terrorist propaganda.
In addition, it would allow much greater sharing of federally held information about activity that "undermines the security of Canada."
The information-sharing measures would permit disclosure of personal data to the private sector and foreign governments, unconstrained by the charter, and open the door to misuse, the association's summary says.
It also says:
— the expanded no-fly list provisions would introduce powers to search computers and mobile devices without a warrant;
— CSIS's powers would be expanded without a similar boost to already insufficient oversight and review of the intelligence sector;
— the bill is being rushed through Parliament without enough time for careful study.
Neither the new disruptive powers nor the information-sharing provisions apply to "lawful" advocacy, protest or dissent, but many critics fear the bill could be used against activists who demonstrate without an official permit or despite a court order.
Public Safety Minister Steven Blaney told the committee last week such concerns were ridiculous, saying the legislation is not intended to capture minor violations committed during legitimate protests.
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